Data networks contain various network devices, such as switches, for sending and receiving data between two locations. For example, frame relay and Asynchronous Transfer Mode (“ATM”) networks contain interconnected network devices that allow data packets or cells to be channeled over a circuit through the network from a host device to a remote device. For a given network circuit, the data from a host location is delivered to the network through a physical circuit such as a T1 line that links to a switch of the network. The remote device that communicates with the host through the network also has a physical circuit to a switch of the network. The communication path between the switches associated with the host and the remote device that passes through the network is a logical circuit.
In frame relay and ATM networks, end devices do not select different routes for data packets or cells sent between the host and the remote location, but always send the data packets or cells through the same path. A host device may have many logical circuits, such as permanent virtual circuits (“PVCs”) or switched virtual circuits (“SVCs”), linked to many remote locations. For example, a PVC sends and receives data packets or cells through the same path leading to the switch of the remote device's physical connection.
In large-scale networks, the host and remote end devices of a network circuit may be connected across different local access and transport areas (“LATAs”) which may in turn be connected to one or more Inter-Exchange Carriers (“IEC”) for transporting data between the LATAs. These connections are made through physical trunk circuits utilizing fixed logical connections known as Network-to-Network Interfaces (“NNIs”).
Periodically, failures may occur to the trunk circuits or the NNIs of network circuits in large-scale networks causing lost data. Currently, such network circuit failures are handled by dispatching technicians on each end of the network circuit (i.e., in each LATA) in response to a reported failure. The technicians manually access a logical element module to troubleshoot the logical circuit portion of the network circuit. The logical element module communicates with the switches in the data network and provides the technician with the status of the logical connections which make up the logical circuit. Once the technician determines the status of a logical connection at one end of a logical circuit (e.g., the host end), the technician then must access a network database to determine the location of the other end of the logical circuit so that its status may also be ascertained. If the technician determines the logical circuit is operating properly, the technician then accesses a physical element module to troubleshoot the physical circuit portion of the network circuit to determine the cause of the failure and then repair it.
Current methods of determining network circuit failures, however, suffer from several drawbacks. One drawback is that troubleshooting the logical and physical circuits is time consuming and results in dropped data packets or cells until the failure is isolated and repaired. For example, isolating a logical circuit failure requires that a technician access a database to identify the logical connections which make up the logical circuit. Once the logical connections are identified, their status is ascertained and the logical circuit is repaired. The database records, however, are manually entered and thus subject to human error which, if present, increases circuit downtime until the logical connections making up the failed logical circuit are identified. Furthermore troubleshooting the physical circuit often requires taking the network circuit out of service to perform testing, thus increasing the downtime and loss of data in the network circuit.
It is with respect to these considerations and others that the present invention has been made.